CN117002122A

CN117002122A - Decorative sheet

Info

Publication number: CN117002122A
Application number: CN202311104546.7A
Authority: CN
Inventors: 山崎祥美; 长岛麻美; 长滨正光; 高桥昌利
Original assignee: Toppan Printing Co Ltd
Current assignee: Toppan Inc
Priority date: 2018-12-19
Filing date: 2019-12-17
Publication date: 2023-11-07
Also published as: EP3900929A4; EP3900929A1; WO2020129983A1

Abstract

The present application provides a decorative sheet having improved scratch resistance under high load conditions. The decorative sheet of the present embodiment is provided with a raw material layer (7), a transparent resin layer (1) and a surface protection layer (4) in this order, wherein the surface protection layer (4) is composed of a plurality of layers, and when the surface protection layer located on the outermost surface among the surface protection layers (4) is used as a surface protection layer (4 a), and the surface protection layer located on the lower layer thereof is used as a surface protection layer (4 b), the surface protection layer (4 a) comprises: an ionizing radiation-curable resin having a corrosion rate E of not less than 1 and not more than 0.30 [ mu ] m/g and not more than 0.6 [ mu ] m/g in a range of not less than 95/5 and not more than 40/60 as measured using a polygonal alumina powder having an average particle diameter (D50) of not less than 1.2 [ mu ] m.

Description

Decorative sheet

The application is a divisional application of application number 2019800836743, application date 2019, 12 month 17, and application name "decorative sheet".

Technical Field

The present application relates to a decorative sheet.

Background

In recent years, as shown in patent documents 1 to 3, for example, there have been proposed a number of decorative sheets using an olefin resin as a decorative sheet in place of a polyvinyl chloride decorative sheet.

However, since these decorative sheets do not use vinyl chloride resin, although the generation of toxic gas or the like at the time of incineration is suppressed, when, for example, ordinary polypropylene sheets or soft polypropylene sheets are used, scratch resistance (mar resistance) of the surface tends to deteriorate. Therefore, a decorative sheet using an olefin resin is sometimes inferior to a conventional polyvinyl chloride decorative sheet in terms of scratch resistance.

Prior art literature

Patent literature

Patent document 1: japanese patent No. 3271022

Patent document 2: japanese patent No. 3861472

Patent document 3: japanese patent No. 3772634

Disclosure of Invention

Problems to be solved by the invention

In order to improve the scratch resistance of the decorative sheet, a method of applying an ionizing radiation curable resin to a surface protective layer and curing the resin is known. However, the decorative sheet is not completely intact, and there is a problem that the decorative sheet is damaged when the scratch resistance test is performed under a high load condition.

Therefore, in order to improve the scratch resistance under high load conditions, a method of making the surface protective layer harder and thicker has been proposed, but there is a problem that when the surface protective layer is too hard, the surface protective layer becomes brittle, impact resistance against falling objects and the like is deteriorated, or weather resistance is deteriorated, and when the surface protective layer becomes thicker, it takes a lot of cost.

In addition, in order to improve the scratch resistance under high load conditions, as in the case of the surface protective layer, a method of making a transparent resin layer located under the surface protective layer harder and thicker has been proposed, but there is also a problem that when the transparent resin layer is too hard, the transparent resin layer becomes brittle, impact resistance against falling objects and the like is deteriorated, or weather resistance is deteriorated, and when the transparent resin layer becomes thicker, it takes a lot of costs.

In addition, in order to improve the scratch resistance under high load conditions, a method of adding an inorganic filler to a surface protective layer has been proposed, but there is also a problem that when an inorganic filler is added to a surface protective layer, the inorganic filler protrudes largely from the surface protective layer, or in the case where there is a void at the interface with the surface protective layer, the inorganic filler is broken at the time of performing the scratch resistance test, or the inorganic filler is detached from the surface protective layer, thereby causing a change in gloss.

The present invention has been made in view of the above-described aspects, and an object thereof is to provide a decorative sheet having improved scratch resistance under high load conditions.

Means for solving the problems

As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by forming at least one of a surface protective layer and a transparent resin layer having a specific corrosion rate on a decorative sheet.

The decorative sheet according to one embodiment of the present invention is a decorative sheet comprising a raw material layer (original), a transparent resin layer, and a surface protective layer in this order, wherein the surface protective layer is composed of a plurality of layers, and when the surface protective layer located on the outermost surface among the surface protective layers is the 1 st surface protective layer and the surface protective layer located below the surface protective layer is the 2 nd surface protective layer, the 1 st surface protective layer comprises 1 or more ionizing radiation curable resins having a corrosion rate E in the range of 0.10 μm to 0.45 μm/g inclusive and 1 or more thermosetting resins having a corrosion rate E in the range of 0.30 μm to 0.6 μm/g inclusive, and the mass ratio of the ionizing radiation curable resins to the thermosetting resins (ionizing radiation curable resins/thermosetting resins) is 95/5 to 40/60.

Further, according to another aspect of the present invention, there is provided a decorative sheet comprising a raw material layer (original layer), a transparent resin layer, and a surface protective layer in this order, wherein the surface protective layer is composed of a plurality of layers, and the corrosion rate E of the 1 st surface protective layer, measured using polygonal alumina particles having an average particle diameter (D50) of 1.2 μm, is in the range of 0.1 μm/g to 0.4 μm/g when the surface protective layer located on the outermost surface among the surface protective layers is the 1 st surface protective layer and the surface protective layer located below is the 2 nd surface protective layer.

Further, according to another aspect of the present invention, there is provided a decorative sheet comprising a raw material layer (raw material), a transparent resin layer, and a surface protective layer in this order, wherein the corrosion rate E of the transparent resin layer measured using polygonal alumina particles having an average particle diameter (D50) of 1.2 μm is in a range of 0.05 μm to 2 μm.

Effects of the invention

According to the decorative sheet of one embodiment of the present invention, a decorative sheet having excellent scratch resistance even under high load conditions can be provided.

Drawings

Fig. 1 is a schematic cross-sectional view showing one example of the structure of a decorative sheet according to an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view showing an example of the structure of a decorative sheet according to another embodiment of the present invention.

Detailed Description

Hereinafter, a decorative sheet according to an embodiment of the present invention will be described in detail with reference to fig. 1 and 2.

The drawings are schematic, and the relationship between the thickness and the planar dimension, the thickness ratio of each layer, and the like are different from those in reality. The following embodiments illustrate a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited to the materials, shapes, structures, and the like of the constituent members described below. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

(measurement of Corrosion Rate E)

First, the "etching rate E" defined in the present embodiment will be described.

The corrosion rate E in the present embodiment is a value measured using, for example, a material surface accuracy tester (micropulp jet corrosion tester, hereinafter referred to as MSE tester, manufactured by Palmeso corporation/device name nano MSE/model N-MSE-a). In addition, the specific measurement method of the corrosion rate E is as follows.

Average particle diameter D ₅₀ Polygonal alumina powder (polygonal alumina particles) of =1.2 μm was dispersed in water to prepare a slurry including 3 mass% of the polygonal alumina powder relative to the total mass of the slurry. Fixing a decorative sheet to the base, and spraying the slurry between the decorative sheet and a nozzle for spraying the slurryThe distance was set to 4mm. The nozzle diameter of the nozzle was 1mm×1mm. A slurry containing polygonal alumina powder is sprayed from a nozzle, and decorative sheets fixed to a base are sequentially etched away from a surface protective layer. The conventional Si wafer or PMMA substrate was etched under the same test conditions in advance, and the standard projection force X was obtained from the displacement etched away with respect to the slurry ejection amount (i.e., the depth cut when 1g of the slurry was ejected), and the ejection intensity at this time was determined from this value. In the present embodiment using polygonal alumina powder, the projection force when 6.360 μm/g was etched away from the conventional Si wafer was set as the standard projection force X.

In the present embodiment, in the case of the polygonal alumina powder, the projection force is x=1/100 (projection force when 0.064 μm/g is etched away from the conventional Si wafer).

After the corroded part is washed by water, the corrosion depth, namely the corrosion depth Z, is measured. The etching depth Z was measured using, for example, a stylus surface shape measuring instrument (model PU-EU 1/stylus tip R=2 μm/load 100. Mu.N/measurement magnification 10,000/measurement length 4 mm/measurement speed 0.2mm/sec, made by Seisakusho, inc.). In the present embodiment, the erosion rate E (μm/g) is calculated using the projected particle amount X' (g) and the erosion depth Z (μm) calculated from the projection force.

It is known that the etching rate E is not affected by the magnitude of the etching rate E of the lower layer existing in the depth direction when the etching rate E is measured. Therefore, when the corrosion rate E is measured, the MSE test may also be performed sequentially from the 1 st surface protective layer located on the outermost surface.

In the present embodiment, each of the corrosion rates E of the ionizing radiation curable resin and the thermosetting resin constituting the surface protective layer was measured by measuring the corrosion rate E of the layer formed only of the ionizing radiation curable resin and the layer formed only of the thermosetting resin, respectively.

(Structure of decorative sheet)

Hereinafter, each structure of the decorative sheet of the present embodiment will be described. In the present embodiment, the case where the surface protection layer is assumed to be 2 layers will be described.

The decorative sheet shown in fig. 1 includes, in order from the top side of the figure, a surface protective layer (1 st surface protective layer) 4a, a surface protective layer (2 nd surface protective layer) 4b, a transparent resin layer 1, an adhesive layer 6 (thermosensitive adhesive layer, anchor coat layer, dry lamination adhesive layer), a pattern layer 2, a raw material layer 7, and a primer layer 5. More specifically, the decorative sheet of the present embodiment is structured such that the patterned layer 2 is provided on one surface of the transparent resin layer 1, and the surface protective layers (the surface protective layer 4a and the surface protective layer 4 b) 4 are provided on the other surface of the transparent resin layer 1.

The decorative sheet shown in fig. 2 includes, in order from the top side of the figure, a surface protective layer (1 st surface protective layer) 4a, a surface protective layer (2 nd surface protective layer) 4b, a transparent resin layer 1, an adhesive resin layer 8, an adhesive layer (heat-sensitive adhesive layer, anchor coat layer, dry lamination adhesive layer) 6, a pattern layer 2, a raw material layer 7, and a primer layer 5. More specifically, the decorative sheet of the present embodiment has a structure in which the patterned layer 2 and the concealing layer 3 are provided on one surface of the transparent resin layer 1, and the surface protective layer 4 is provided on the other surface of the transparent resin layer 1.

In order to improve the design, the embossed pattern 1a may be provided on the surface of the transparent resin layer 1 on the surface protection layer 4b side.

Further, the total thickness of the decorative sheet may be in the range of 80 μm to 250 μm.

The decorative sheet of the present embodiment preferably does not contain a polyvinyl chloride resin. By using a decorative sheet made of a non-polyvinyl chloride resin, the concern of toxic gas generation during incineration can be reduced.

The layers constituting the decorative sheet according to the present embodiment will be described in detail below.

< raw Material layer >)

When the raw material layer (raw material) 7 imparts design properties, flaw resistance and post-processing resistance to the decorative sheet, it is possible to appropriately select and use a synthetic resin such as polyethylene, polypropylene, polystyrene, polybutylene, polycarbonate, polyester, polyethylene terephthalate, polybutylene terephthalate, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, acrylic acid, or a foam of such a synthetic resin, ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene-styrene block copolymer rubber, polyurethane, or the like, or a rubber such as an organic or inorganic nonwoven fabric, synthetic paper, aluminum, iron, gold, silver, or the like. The raw material layer 7 may be a sheet made of the same resin composition as the transparent resin layer 1. Among the above, polyolefin materials such as polypropylene and polyethylene are preferable.

Examples of the polyolefin-based resin contained in the raw material layer 7 include: in addition to polypropylene, polyethylene, polybutylene, and the like, there are included homopolymers of alpha olefins (e.g., propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-hexene, 4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, and the like) or copolymers of 2 or more, ethylene/vinyl acetate copolymers, ethylene/vinyl alcohol copolymers, ethylene/methyl methacrylate copolymers, ethylene/ethyl acrylate copolymers, ethylene/butyl acrylate copolymers, and the like.

When a substrate having no surface activity such as a polyolefin material is used as the raw material layer 7, it is preferable to perform, for example, corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, dichromic acid treatment, or the like on the front and back surfaces of the raw material layer 7. A primer layer (not shown) for ensuring the confidentiality may be provided between the raw material layer 7 and the patterned layer 2.

In the case where the decorative sheet is to be provided with concealing properties, a concealing colored sheet may be used for the raw material layer 7, and as shown in fig. 2, the concealing layer 3 may be provided on the upper layer of the raw material layer 7 and on the lower layer of the pattern layer 2. When a coloring sheet is used as the raw material layer 7, a colorant may be added to the resin material constituting the raw material layer 7 to perform coloring. As the colorant, for example, in addition to an inorganic pigment (titanium oxide, carbon black, or the like) and an organic pigment (phthalocyanine blue, or the like), a dye may be used. The colorant of the present embodiment may be used by selecting 1 or 2 or more from known or commercially available colorants, and the addition amount may be adjusted to obtain desired hiding and design properties.

Various additives such as a filler, a foaming agent, a flame retardant, a lubricant, an antistatic agent, an antioxidant, a crystal nucleus agent, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a colorant, and a matting agent may be added to the raw material layer 7 as necessary.

The thickness of the raw material layer 7 is preferably in the range of 30 μm to 150 μm in view of printing operability and cost.

< Pattern layer/hidden layer >)

As a method of providing the patterned layer 2 and the concealing layer 3, there are the following methods: gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, inkjet printing, or the like, for example, is performed on the raw material layer 7 or the transparent resin layer 1. In particular, when the concealing layer 3 is applied, for example, a comma coater, a blade coater, a slit coater, a metal vapor deposition, a sputtering method, or the like can be used. The concealing layer 3 is usually provided on the upper layer of the raw material layer 7 and the lower layer of the pattern layer 2.

When the patterned layer 2 is formed using an ink, the binder contained in the ink may be appropriately selected from, for example, each or each modification of nitrocotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, and the like. These are aqueous, solvent-based, or emulsion-based, and may be any one-pack type or two-pack type using a curing agent.

The ink may be cured by irradiation with ultraviolet rays, electron beams, or the like. Among them, the most common method is a method of using urethane-based ink and curing it by isocyanate.

In addition to the above binder, a colorant such as a pigment or a dye, an extender pigment, a solvent, and various additives contained in a general ink may be added. Particularly commonly used pigments include, for example, condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolinone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, mica and like pearl pigments and the like. In addition to the application of the ink, the design may be performed by vapor deposition and sputtering of various metals.

The material used in the masking layer 3 may be substantially the same material as the patterned layer 2. Since the concealing layer 3 needs to have concealing properties for its purpose, it is preferable to use, for example, an opaque pigment, titanium oxide, iron oxide, or the like as the pigment. In order to improve the concealing property, a metal such as gold, silver, copper, or aluminum may be added. In general, flake aluminum is often added. When the coating thickness, i.e., the thickness of the concealing layer 3 is less than 2 μm, it is difficult to impart concealing properties, and when it exceeds 10 μm, the cohesive force of the resin layer tends to be weakened. Therefore, the thickness of the concealing layer 3 is suitably in the range of 2 μm or more and 10 μm or less.

< adhesive layer >)

The adhesive layer 6 may be made of any material, and as the bonding method using the adhesive layer 6, thermal lamination, extrusion lamination, dry lamination, and the like, for example, may be used. The adhesive contained in the adhesive layer 6 may be selected from, for example, acrylic, polyester, polyurethane, and the like. In general, the adhesive contained in the adhesive layer 6 is preferably a two-part curable adhesive in view of its cohesive force, and in particular, a urethane material obtained by reacting an isocyanate with a polyol is preferably used.

< adhesive resin layer >)

As shown in fig. 2, an adhesive resin layer 8 may be provided between the adhesive layer 6 and the transparent resin layer 1. In particular, when further lamination strength is required in the extrusion lamination method, the adhesive resin layer 8 is sometimes provided. The transparent resin layer 1 and the adhesive resin layer 8 are usually molded by lamination by a coextrusion method.

The resin contained in the adhesive resin layer 8 is preferably a resin obtained by acid-modifying a resin such as polypropylene, polyethylene, or acrylic, for example, and the thickness thereof is preferably 2 μm or more from the viewpoint of improving the adhesive force. When the thickness of the adhesive resin layer 8 is less than 2 μm, there is a tendency that it is difficult to obtain sufficient adhesive force. In addition, when the thickness of the adhesive resin layer 8 is too large, the surface hardness is intentionally increased by the transparent resin layer 1 having high crystallinity, but it is also affected by the flexibility of the adhesive resin layer 8 itself, so that it is preferably 20 μm or less.

< transparent resin layer >)

The transparent resin layer 1 is formed on the adhesive layer 6 or the adhesive resin layer 8, and the transparent resin layer 1 of the present embodiment is a single layer. By making the transparent resin layer 1 have a specific corrosion rate E, a decorative sheet having excellent scratch resistance in a high load region can be provided.

Hereinafter, the transparent resin layer will be described in detail.

The transparent resin layer 1 is formed by using the average particle diameter (D ₅₀ ) A resin composition having a corrosion rate E of 0.05-2 μm/g as measured on a polygonal alumina powder of 1.2 μm. When the corrosion rate E of the transparent resin layer 1 is less than 0.05 μm/g, it is not preferable because the scratch resistance is significantly lowered. When the corrosion rate E of the transparent resin layer 1 exceeds 2 μm/g, weather resistance and workability are remarkably lowered, and thus it is not preferable. If the average particle diameter (D ₅₀ ) The corrosion rate E of the transparent resin layer 1 measured on the polygonal alumina powder of 1.2 μm is more preferably in the range of 0.1 μm/g to 2 μm/g.

The transparent resin layer 1 may be a sheet formed by film formation, or may be a sheet formed by laminating formed sheets. The transparent resin layer 1 is formed of, for example, a highly crystalline polypropylene resin.

Further, one or both sides of the transparent resin layer 1 may be activated by, for example, corona treatment, plasma treatment, electron beam treatment, ultraviolet treatment, dichromic acid treatment, or the like, as necessary. In addition, if there is a problem in adhesion of the concealing layer 3 to a substrate (a substrate such as a wood board, an inorganic board, or a metal board to which the above decorative sheet is attached), the primer layer 5 may be appropriately provided in a superimposed manner.

When the transparent resin layer 1 is formed from a sheet obtained by film formation, a method using an extruder, for example, is generally used.

When the transparent resin layer 1 is laminated and molded, there is no particular limitation, and a method of applying hot pressing, an extrusion lamination method, a dry lamination method, and the like are generally used, for example. Further, when the embossed pattern 1a is applied, there is a method of: the sheet laminated by various methods at one time is embossed by, for example, hot pressing from the rear, or embossing is performed simultaneously by providing a cooling roll with a concave-convex pattern and extrusion lamination using the cooling roll. More specifically, the embossed pattern 1a is directly imparted to, for example, a high crystalline polypropylene sheet as the transparent resin layer 1 by a method comprising: a method of imparting an embossed pattern to the sheet having been formed by heat and pressure using an embossed plate having an embossed pattern, a method of cooling while providing embossing using a cooling roll having an embossed pattern when using an extruder film, or the like. Here, ink may be embedded in the embossed pattern 1a as the embossed portion, thereby further improving the design.

In addition, the embossed pattern 1a may be provided if necessary, and may be not provided if not necessary.

The thickness of the transparent resin layer 1 is preferably in the range of 40 μm to 170 μm. When the thickness of the transparent resin layer 1 is less than 40 μm, weather resistance, scratch resistance may be lowered. When the thickness of the transparent resin layer 1 exceeds 170 μm, the manufacturing cost increases, and the flexibility may decrease.

As necessary, for example, a heat stabilizer, a flame retardant, an ultraviolet absorber, a light stabilizer, an anti-blocking agent, a catalyst scavenger may be added to the transparent resin layer 1, and various additives such as a colorant, a light scattering agent, and a gloss adjuster may be added within a range that does not impair the characteristics of the present embodiment.

Generally, phenols, sulfur, phosphorus, hydrazine, etc., as heat stabilizers, aluminum hydroxide, magnesium hydroxide, etc., as flame retardants, benzotriazole, benzoate, benzophenone, triazine, etc., as ultraviolet absorbers, etc., and hindered amines, etc., as light stabilizers, etc., are added in any combination. In particular, in the case of using the resin composition for the present application, it is necessary to consider weather resistance, and in this case, an ultraviolet absorber and a light stabilizer may be added to the transparent resin layer 1, and the transparent resin layer 1 may be appropriately added in an amount of 0.1 mass% to 2.0 mass%, respectively, based on 100 mass%.

The transparent resin layer 1 may contain a crystallization nucleating agent (nano-sized nucleating agent) after the vesicular treatment by the supercritical reverse phase evaporation method.

In a specific vesicular treatment by the supercritical reverse phase evaporation method, an aqueous phase is injected into a mixed fluid of supercritical carbon dioxide, a phospholipid as a dispersing agent, and an additive as an encapsulating material, and an emulsion of the supercritical carbon dioxide and the aqueous phase is produced by stirring. When the pressure is reduced, the carbon dioxide expands and evaporates to generate a phase change, and a nanocapsule in which the surface of the additive particles is covered with a single-layer film of phospholipid is formed. By using this supercritical reverse phase evaporation method, unlike the conventional encapsulation method in which a dispersant forms multiple films on the surface of an additive particle, a capsule of a single-layer film can be easily formed, and thus a capsule of a smaller diameter can be produced. In addition, when a capsule of multiple membranes is desired, it can be easily prepared by injecting supercritical carbon dioxide into a mixed fluid of phospholipids, additives, and an aqueous phase. Examples of phospholipids used in the preparation of vesicles include phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiolipin, egg yolk lecithin, hydrogenated egg yolk lecithin, soybean lecithin, hydrogenated soybean lecithin and other glycerophospholipids, sphingomyelin, ceramide phosphoethanolamine, ceramide phosphoglyceride and other sphingomyelins. The vesicle has an outer membrane formed of a phospholipid, and thus can achieve excellent compatibility with a resin material.

When the transparent resin layer 1 is made of a resin layer containing the above-described nano-sized nucleating agent, it is important to contain crystalline polypropylene resin as a main component in a range of 90 mass% to 100 mass% and contain the nucleating agent as a nano-sized additive. More preferably, the nano-sized additive is contained in the vesicle state (nucleator vesicle). In this case, the average particle diameter of the nucleating agent vesicles is preferably 1/2 or less of the wavelength of visible light. Specifically, since the wavelength region of visible light is 400 to 750nm, the average particle diameter of the nano-sized nucleating agent is preferably 375nm or less. It is important that in such a transparent resin layer 1, the haze value is set to 15% or less, more preferably 10% or less, the tensile elastic modulus is set to be in the range of 800MPa to 2,000MPa, and the tensile elongation at break is set to be 200% or more by adjusting the cooling conditions at the time of film formation.

The crystalline polypropylene resin may be appropriately selected from isotactic polypropylene, syndiotactic polypropylene, atactic polypropylene, and block polypropylene having different pentad fraction. More preferably, it is important that the crystalline polypropylene resin is a homopolymer of propylene having an isotactic pentad fraction (mmmm fraction) of 95% or more, more preferably 96% or more, that is, a high-crystalline homopolypropylene resin as a homopolymer. In addition, as long as the physical properties of the crystalline polypropylene are not significantly adversely affected, resins other than the crystalline polypropylene constituting the transparent resin layer 1 may be appropriately selected depending on the purpose of mixing thereof. However, in order to maintain the V-groove bending workability, a resin having good compatibility with the crystalline polypropylene resin constituting the transparent resin layer 1 is preferable.

Thus, the thickness of the transparent resin layer 1 is preferably in the range of 20 μm to 250 μm. More preferably in the range of 40 μm to 170 μm.

By making the particle diameter extremely small to the nano-size, the amount and surface area of the nucleating agent present per unit volume increase inversely proportional to the cubic of the particle diameter. As a result, when the distance between the respective nucleating agent particles is short and crystal growth starts from the surface of 1 nucleating agent particle when the nucleating agent particles are added to the polypropylene resin, the end portions of the crystals grown are immediately in contact with the end portions of the crystals grown from the surface of the other nucleating agent particle adjacent to the nucleating agent particle, and the end portions of the crystals are prevented from growing to stop the growth of the respective crystals, so that the average particle diameter of the spherulites in the crystal portion of the crystalline polypropylene resin can be made extremely small.

Therefore, by containing the nano-sized nucleating agent in the transparent resin layer 1, a larger number of crystal nuclei are generated in the resin than in the conventional nucleating agent, and as a result, the distance between the crystal nuclei in the crystal portion is shortened, and the growth of each crystal is successfully suppressed and the average particle diameter of the spherulites becomes extremely small. Further, such crystalline polypropylene resins have extremely high transparency, such that the haze value is 15% or less.

Further, by containing the nano-sized nucleating agent in the form of a vesicle, i.e., a nucleating agent vesicle, aggregation between the nucleating agents is prevented, and high dispersibility against a resin material is achieved. In the resin composition, the outer film of the nucleating agent vesicle is partially disintegrated to expose the nucleating agent, and during crystallization of the resin material, spherulites having nano-sized nucleating agent particles as crystallization nuclei are formed.

In this case, in particular, the nucleating agent vesicles obtained by the supercritical reverse phase evaporation method have extremely small sizes. Therefore, the average particle diameter of spherulites in the crystal portion of the crystalline polypropylene resin can be made extremely small, and the crystallinity of the crystal portion can be significantly improved.

In the decorative sheet of the present embodiment, the transparent resin layer 1 contains a nano-sized nucleating agent, more preferably a nucleating agent vesicle, so that the average particle diameter of spherulites in the crystal portion of the crystalline polypropylene resin is extremely small, thereby achieving excellent scratch resistance. In particular, by containing the nucleating agent vesicles in the transparent resin layer 1, the nucleating agent can be uniformly dispersed in the crystalline polypropylene resin, and the crystallinity of the crystalline polypropylene is controlled to adjust the hardness and toughness of the transparent resin layer 1 to be optimal. Further, by incorporating the nucleating agent vesicles in the transparent resin layer 1, excellent fracture resistance and post-processing resistance can be achieved in which the tensile elastic modulus is in the range of 800MPa to 2000MPa and the tensile elongation at break is 200% or more.

Hereinafter, terms used in the above description are briefly described.

The nucleating agent is a substance that promotes the formation of crystallization nuclei during crystallization of the resin, or is added to crystallize the nucleating agent itself. Nucleating agents are of the following types: a molten type in which the nucleating agent is melted in the resin of the base material and precipitated again to form a crystalline nucleus, or a non-molten type in which the nucleating agent added to the base material is not melted and becomes a crystalline nucleus with the original particle diameter. Examples of the nucleating agent for the polypropylene resin include metal phosphate, metal benzoate, metal pimelate, metal rosin, benzylidene sorbitol, quinacridone, phthalocyanine blue, talc, and the like. In particular, in the present embodiment, in order to obtain the effect of the nanocrystallization to the maximum, a phosphate metal salt, a benzoate metal salt, a pimelate metal salt, a rosin metal salt, which are non-molten and can be expected to have good transparency, is preferably used, but when the nanocrystallization is performed, colored quinacridone, phthalocyanine blue, talc, or the like can be used. In addition, a melt type benzylidene sorbitol may be appropriately mixed with a non-melt type nucleating agent.

The haze value is a value obtained by subtracting the integral value (linear transmittance) of only the linear component from the light rays emitted from the other surface (total light transmittance) from the integral value of all the light rays emitted from the other surface (diffuse transmittance) when the light incident from the one surface of the object is emitted to the other surface, and dividing the value by the total light transmittance, expressed as a percentage. Therefore, a smaller haze value indicates a higher transparency. The haze value depends on the internal haze determined by the internal state of the object such as the crystallinity of the crystal portion and the spherulitic size, and the external haze determined by the surface state of the object such as the presence or absence of irregularities on the incident surface and the exit surface. In the present embodiment, when referred to as a haze value only, a value determined by the internal haze and the external haze is represented.

The isotactic pentad fraction (mmmm fraction) is obtained by using 13-mass-number carbon C (isotope) ¹³ The C-NMR measurement (nuclear magnetic resonance measurement) is a value calculated from a numerical value (electromagnetic wave absorption rate) obtained by resonating a resin material constituting the transparent resin layer 1 at a predetermined resonance frequency, and defines an atomic arrangement, an electronic structure, and a molecular microstructure in the resin material. The isotactic pentad fraction of polypropylene resin is obtained by ¹³ The ratio of the juxtaposition of 5 propylene units as measured by C-NMR was used as a measure of crystallinity or stereoregularity. Further, such an isotactic pentad fraction is one of important factors mainly determining the scratch resistance of the surface, and fundamentally, the higher the isotactic pentad fraction is, the higher the crystallinity of the sheet is, and thus the scratch resistance is improved.

< surface protective layer >)

The surface protective layer 4 of the present embodiment includes a surface protective layer 4a and a surface protective layer 4b. Since the surface protective layer 4a has a specific corrosion rate E, a decorative sheet having excellent surface scratch resistance can be provided.

Further, the surface protective layer 4a of the present embodiment also has a specific film thickness and static friction coefficient, and by including the inorganic filler subjected to the hydrophobization treatment and the bonding with the surface protective layer 4a is reinforced, a decorative sheet having excellent surface scratch resistance can be provided.

The surface protection layer 4 will be described in detail below.

The surface protection layer 4 is composed of a plurality of layers. In the surface protective layer 4, when the surface protective layer located on the outermost surface is the "surface protective layer 4a", and the surface protective layer located under the surface protective layer 4a is the "surface protective layer 4b", the average particle diameter (D ₅₀ ) The corrosion rate E of the surface protective layer 4a measured on the polygonal alumina powder of 1.2 μm is in the range of 0.1 μm/g to 0.4 μm/g. When the etching rate E of the surface protective layer 4a is less than 0.1 μm/g, the etching rate E becomes small, and the density with the surface protective layer 4b becomes highThe adhesion may be reduced. Therefore, impact resistance may be lowered. When the corrosion rate E of the surface protective layer 4a exceeds 0.4 μm/g, the scratch resistance tends to deteriorate.

Further, the surface protection layer 4a of another embodiment includes: using the average particle diameter (D ₅₀ ) An ionizing radiation-curable resin having a corrosion rate E of 0.10 μm or more and 0.45 μm or less in the range of 1.2 μm or more as measured with a polygonal alumina powder, and a resin having an average particle diameter (D ₅₀ ) 1 or more thermosetting resins having a corrosion rate E, measured on a polygonal alumina powder of 1.2 μm, in a range of 0.30 μm/g or more and 0.6 μm/g or less. Further, the mass ratio of the ionizing radiation curable resin to the thermosetting resin (ionizing radiation curable resin/thermosetting resin) constituting the surface protective layer 4a is 95/5 to 40/60. When the corrosion rate E of the ionizing radiation curable resin is less than 0.10 μm/g, the corrosion rate E of the thermosetting resin is less than 0.30 μm/g, and the ratio of the thermosetting resin is less than 5%, weather resistance is remarkably lowered, and thus it is not preferable. When the corrosion rate E of the ionizing radiation curable resin exceeds 0.45 μm/g, the corrosion rate E of the thermosetting resin exceeds 0.6 μm/g, and the ratio of the thermosetting resin exceeds 60%, the scratch resistance is remarkably lowered, and thus it is not preferable. The surface protection layer 4a and the surface protection layer 4b may be formed of different resins from each other.

Further, in the case where the surface protective layer 4a contains an ionizing radiation curable resin and a thermosetting resin, if an average particle diameter (D ₅₀ ) The corrosion rate E of the surface protective layer 4a measured on the polygonal alumina powder of 1.2 μm is more preferably in the range of 0.2 μm/g to 0.45 μm/g. When the corrosion rate E of the surface protective layer 4a is less than 0.2 μm/g, weather resistance is remarkably lowered, and thus it is not preferable. When the corrosion rate E of the surface protective layer 4a exceeds 0.45 μm/g, the scratch resistance is significantly reduced, and thus it is not preferable.

The thickness of the surface protective layer 4a may be in the range of 2 μm to 7 μm. When the thickness of the surface protective layer 4a is less than 2 μm, productivity is lowered because the coating manner is limited and stable production is difficult. Further, weather resistance and scratch resistance are reduced, and deviation may be increased. When the thickness of the surface protective layer 4a exceeds 7 μm, the balance of performance and cost is broken, and the cost increases. In addition, flexibility decreases.

The thickness of the surface protective layer 4b may be in the range of 2 μm to 14 μm. When the thickness of the surface protective layer 4b is less than 2 μm, productivity is lowered because the coating manner is limited and stable production is difficult. In addition, weather resistance and scratch resistance are reduced, and deviation may become large. When the thickness of the surface protective layer 4b exceeds 14 μm, the balance of performance and cost is broken, and the cost increases. In addition, flexibility decreases.

The thickness of the entire surface protective layer 4 may be in the range of 4 μm to 21 μm. When the thickness of the surface protective layer 4 as a whole is less than 4 μm, productivity is lowered because the coating manner is limited and stable production is difficult. In addition, weather resistance and scratch resistance are reduced, and deviation may become large. When the thickness of the surface protective layer 4 as a whole exceeds 21 μm, the balance of performance and cost is broken, and the cost increases. In addition, flexibility decreases.

The static friction coefficient μs (according to JISK7 125) of the decorative sheet, i.e., the surface protective layer 4a of the present embodiment may be in the range of 0.25 to 0.5. When the static friction coefficient μs of the surface protective layer 4a is less than 0.25, the surface of the surface protective layer 4a as the outermost layer of the decorative sheet is easily slipped and is therefore hardly damaged even under high load conditions, but is not suitable in terms of an increased risk of slipping of a person when used as a floor. When the static friction coefficient μs of the surface protective layer 4a exceeds 0.5, the friction between an object contacting the sheet surface and the sheet surface increases, and therefore the surface tends to be easily damaged under high load conditions.

The method of providing the surface protection layer 4 is the same as the method of providing the concealing layer 3 and the patterned layer 2, and is not limited.

The surface protective layer 4 preferably includes an ionizing radiation-curable resin that is a resin cured by ultraviolet or electron beam irradiation, and a thermosetting resin that is a resin cured by heat. More specifically, the surface protective layer 4 preferably includes 1 or more ionizing radiation curable resins and 1 or more thermosetting resins. The content of the ionizing radiation-curable resin may be in the range of 65 parts by mass to 100 parts by mass of the resin constituting the surface protective layer 4, particularly the surface protective layer 4 a. When the content of the ionizing radiation-curable resin is less than 65 parts by mass, the corrosion rate E increases and the scratch resistance decreases.

The thermosetting resin may be appropriately selected from, for example, polyurethanes, acrylics, silicones, fluorides, epoxies, ethylenes, polyesters, melamine, amino alcohols, urea, and the like. The form may be any of aqueous, emulsion, and solvent, and the curing may be one-liquid type or two-liquid type using a curing agent. Among these, from the viewpoints of handleability, price, cohesive force of the resin itself, and the like, a top coat layer of urethane type utilizing isocyanate reaction is preferable.

The isocyanate may be appropriately selected from, for example, toluene Diisocyanate (TDI), xylene Diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine Diisocyanate (LDI), isophorone diisocyanate (IPDI), adducts of derivatives of bis (isocyanatomethyl) cyclohexane (HXDI), trimethylhexamethylene diisocyanate (TMDI), etc., biuret, isocyanurate, various prepolymers, etc., and the like, and when weather resistance is considered, it is preferable to use a curing agent based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI) having a linear molecular structure.

The ionizing radiation curable resin may be appropriately selected from, for example, polyester acrylates, epoxy acrylates, urethane acrylates, acrylic acrylates, and the like, and particularly, urethane acrylates and acrylic acrylates having excellent weather (light) resistance are preferably used. From the viewpoint of operability, as a curing method of the ionizing radiation curable resin, curing by active energy rays such as ultraviolet rays and electron beams is preferable.

As the electron beam source, for example, a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light, or a metal halide lamp can be used. The wavelength of the ultraviolet light is preferably 180nm to 400nm.

As for the mixture of the thermosetting resin and the ionizing radiation curable resin, for example, a urethane resin obtained by reacting an acrylic polyol as the thermosetting resin with an isocyanate is more preferably used in combination with a urethane acrylate resin as the ionizing radiation curable resin. By using a mixture of a thermosetting resin and an ionizing radiation curable resin, it is possible to improve the surface hardness while at the same time at least 1 of suppression of curing shrinkage and improvement of the adhesion of inorganic fine particles (inorganic filler) can be achieved.

The ionizing radiation-curable resin constituting the surface protective layer 4, particularly the surface protective layer 4a, may contain 1 or more component having 6 or more functional groups and a mass average molecular weight of 1,000 or more. More preferably, the composition contains 1 or more components having 6 or more functional groups and a mass average molecular weight of 1,000 to 20,000. When the functional group of the ionizing radiation curable resin is less than 6, the bridge density becomes small, and the scratch resistance is remarkably lowered, which is not preferable. When the mass average molecular weight of the ionizing radiation curable resin is less than 1,000, it is not preferable because the surface state at the time of coating is significantly deteriorated. When the mass average molecular weight of the ionizing radiation curable resin exceeds 20,000, the coating suitability is remarkably lowered due to an increase in the viscosity of the coating liquid, and thus it is not preferable.

The resin other than the ionizing radiation curable resin, for example, a thermosetting resin has a higher corrosion rate E than the ionizing radiation curable resin.

In addition, in order to improve weather resistance, an ultraviolet absorber and a light stabilizer may be appropriately added to the surface protective layer 4, particularly the surface protective layer 4 a. In order to impart various functions, functional additives such as an antibacterial agent and a mildew preventive may be optionally added.

In the present embodiment, the case where the surface protective layer 4 is formed of a resin including an ionizing radiation curable resin and a thermosetting resin has been described, but the present embodiment is not limited to this. The surface protective layer 4 may be a layer formed only of an ionizing radiation curable resin, or may be a layer formed only of a thermosetting resin.

In order to improve the scratch resistance of the surface or to adjust the gloss as the design is imparted, it is preferable to add an inorganic filler to the surface protective layer 4.

As the inorganic filler, for example, alumina, silica, boehmite, iron oxide, magnesium oxide, aluminosilicate, diamond, silicon nitride, silicon carbide, glass beads, calcium titanate, barium titanate, magnesium pyrophosphate, zinc oxide, silicon nitride, zirconium oxide, chromium oxide, iron oxide, glass fiber, and the like can be added. As the inorganic filler, inorganic fine particles having an average particle diameter of 1 μm or more and 30 μm or less can be used, and inorganic fine particles having an average particle diameter of 1 μm or more and 10 μm or less are particularly preferable. When the average particle diameter of the inorganic filler is less than 1. Mu.m, it tends to be difficult to obtain a matting effect. This is because, in order to exert the matting effect, it is desirable that the particle diameter is the same as or larger than the thickness of the film (layer) to which the inorganic filler is added. When the average particle diameter of the inorganic filler exceeds 30 μm, more precisely, exceeds 10 μm, the inorganic filler tends to fall off from the surface protective layer 4 under high load conditions, and the gloss changes to cause the surface to look deteriorated.

For example, when gravure printing is selected, a coating thickness of one layer is generally from 2 μm to 12 μm is suitable. In this case, as described above, it is preferable to select an inorganic filler having an average particle diameter to the same extent as the thickness of the one-time coatable material or less. However, when the surface protective layer 4 is made of multiple layers, an inorganic filler having an average particle diameter larger than the film thickness of the surface protective layer 4b located below may be added.

The content of the inorganic filler may be in the range of 1 part by mass to 20 parts by mass with respect to 100 parts by mass of the resin constituting the surface protective layer 4 a. When the content of the inorganic filler is less than 1 part by mass, the scratch resistance is lowered. When the content of the inorganic filler exceeds 20 parts by mass, the designability may be impaired because the gloss of the surface is significantly reduced. In addition, weather resistance and stain resistance may be reduced.

Preferably, the inorganic filler is surface-treated. The surface treatment of the inorganic filler can strengthen the bond with the surface protective layer 4. The surface protective layer 4 such as the surface protective layer 4b may be added with an inorganic filler having an untreated surface.

Further, when the surface treatment is performed, it is preferable to have a functional group imparting hydrophobization to the surface of the inorganic filler and reactivity with the surface protective layer 4. That is, the surface treatment agent for treating the surface of the inorganic filler preferably has a reactive group that reacts with the main agent resin constituting the surface protective layer 4, particularly the surface protective layer 4 a.

When the surface treatment of the inorganic filler is performed, the method is not particularly limited, and a known method may be selected.

As the surface treatment agent for the surface treatment of the inorganic filler, at least 1 of a surfactant, a fatty acid metal salt, a silane coupling agent, silicone, wax, and a modified resin can be used. The surface treatment agent of the present embodiment may be selected from, for example, a silicone oil type, an alkylsilazane type, a trimethylsilylating agent, an alkoxysilane type, a siloxane, a silane coupling agent, a titanium coupling agent, a phosphoric acid type/fatty acid type surfactant, or the like, and may be 1 type or a combination of a plurality of types.

As the silicone oil-based treating agent, for example, linear silicone oil (dimethylsilicone oil, methylphenylsilicone oil, etc.), modified silicone oil (amino-modified, epoxy-modified, carboxyl-modified, methanol-modified, methacrylic-modified, mercapto-modified, phenol-modified, single terminal reactive-modified, heterogeneous functional-group-modified, polyether-modified, methylstyrene-based-modified, alkyl-modified, higher fatty acid ester-modified, hydrophilic-specific-modified, higher alkoxy-modified, higher fatty acid-containing-modified, fluorine-modified silicone oil, etc.), can be selected.

As the alkylsilazane-based treating agent, hexamethyldisilazane, vinyl silazane, or the like, for example, may be selected.

Examples of the silane coupling agent include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-octyltriethoxysilane, n-hexyltriethoxysilane, decyltriethoxysilane, phenyltriethoxysilane, benzyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, diethoxymethylphenylsilane, allyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, and chlorosilane compounds such as trimethylchlorosilane and diethyldichlorosilane.

As the trimethylsilylating agent, an alkoxysilane compound in the silane coupling agent may be selected.

As the titanate coupling agent, for example, isopropyl tridecyl benzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2, 2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctyl pyrophosphate) oxy titanate, and the like can be selected.

As the aluminate coupling agent, for example, diisopropylaluminum acetoacetate or the like can be selected.

As the surfactant, anionic, cationic, nonionic, amphoteric surfactants, and the like can be selected.

The above surface treating agent is dispersed by the above supercritical reverse phase evaporation method and then used for surface treatment to increase the reaction rate at the time of surface treatment.

The surface-treated filler can be obtained by using a surface-treating agent treated by a supercritical reverse phase evaporation method and performing surface treatment by a known method.

As described above, one of the features (specific matters of the invention) of the decorative sheet of the present embodiment is that "the surface treatment agent for treating the surface of the inorganic filler is a surface treatment agent-encapsulated vesicle in which the surface treatment agent is encapsulated in the vesicle by the supercritical reverse phase evaporation method". Further, the effect of significantly improving the reactivity of the surface treatment agent with the inorganic filler is exhibited by reacting with the inorganic filler in a state in which the surface treatment agent is encapsulated in the vesicle, but it is conceivable that it is difficult, if not impossible, to directly define the feature by using the structure or characteristics of the object in a state of the finished decorative sheet. The reason for this is as follows. The surface treatment agent added in the state of vesicles has high dispersibility and is in a dispersed state, and reacts with the inorganic filler with high reaction probability. However, in the decorative sheet manufacturing step after the surface treatment agent is reacted with the inorganic filler in the state of the vesicle to manufacture the surface protective layer, various treatments such as compression treatment and curing treatment are generally performed on the laminate, but due to such treatments, there is a high possibility that the outer film of the vesicle encapsulating the surface treatment agent breaks or chemically reacts, and the outer film does not contain (encapsulate) the surface treatment agent, and the state of breaking or chemically reacting the outer film varies depending on the treatment step of the decorative sheet. In addition, in the case where the surface treatment agent or the like is not contained in the outer film, it is difficult to determine the physical properties themselves by the numerical range, and it is conceivable that: it may be difficult to judge whether the constituent material of the broken outer membrane is the outer membrane of the vesicle or a material added separately from the surface treatment agent. Thus, although the present invention is different from the conventional one in that the reactivity of the surface treatment agent with the inorganic filler is significantly improved, it is conceivable that: whether or not to add in a state of a vesicle encapsulating a surface treatment agent, which is impractical to determine by analyzing the resulting numerical range based on measuring its structure or characteristics in a state of a decorative sheet.

As described above, the surface treatment method of the inorganic filler is not particularly limited. As a method of surface treatment, a method generally used may be selected from any one of a dry method, a wet method, and a bulk mixing method (integral blend method). In the dry method, a surface treatment agent diluted with water or an organic solvent is added to an inorganic filler having no surface treatment by spraying or the like, followed by stirring and curing, and the reaction is carried out to obtain a surface-treated filler.

In addition, when the embossed pattern 1a is applied on the surface of the transparent resin layer 1 on the surface protective layer 4 side, the ink forming the surface protective layer 4a may be buried in the embossed pattern 1a by a wiping process to improve the designability.

In view of weather resistance, in order to protect the transparent resin layer 1 as a base material, there is also a method of imparting weather resistance to the surface protection layer 4 and the transparent resin layer 1, respectively, as described above. In addition, there is a method of adding an ultraviolet absorber and a light stabilizer to the adhesive resin layer 8, the adhesive layer 6, and the patterned layer 2 itself, respectively, in order to protect the patterned layer 2.

The amount of the photoinitiator to be added is not particularly limited, but is preferably about 0.1 to 15 parts by mass based on 100 parts by mass of the main resin.

The kind of photoinitiator is not particularly limited. In the case of resins having a radically polymerizable unsaturated group, as the photoinitiator, at least 1 of acetophenones, benzophenones, thioxanthones, benzoin methyl ether, michael benzoyl benzoate, michiuron, diphenyl sulfide, dibenzyldisulfide, diethyl oxide, triphenylbisimidazole, isopropyl-N, N-dimethylaminobenzoate, and the like can be selected, for example. Furthermore, depending on the light source or the production environment, various combination designs are preferred.

In the case of resins having a cationically polymerizable functional group, at least 1 of, for example, an aromatic diazonium salt, an aromatic sulfonium salt, a metallocene compound, benzoin sulfonate, and a furyloxy sulfoxonium diallyl iodonium salt (furyloxysulfoxonium diaryliodonium salt) may be selected as the photoinitiator.

< primer layer >

The material used for the primer layer 5 may be substantially the same material as the patterned layer 2 or the concealing layer 3. In addition, when it is considered to wind in a net shape to apply to the back surface of the decorative sheet, an inorganic filler such as silica, alumina, magnesia, titania, barium sulfate, etc. may be added to the primer layer 5 in order to avoid blocking and improve adhesion with the adhesive. The thickness of the primer layer 5, which is the coating thickness, is preferably in the range of 0.1 μm to 10.0 μm, more preferably in the range of 0.1 μm to 3.0 μm, in order to ensure adhesion to the raw material layer 7 serving as a base material.

The primer layer 5 is required in the case where the surface of the raw material layer 7 is inactive such as an olefin-based material, but the primer layer 5 is not particularly required in the case where the surface is an active substrate.

Examples (example)

(example 1)

Hereinafter, specific embodiments of the decorative sheet of the present invention are discussed.

In examples 1-1 to 1-4 and comparative examples 1-1 to 1-2, the same materials were used except for the surface protective layer 4a, and all up to the surface protective layer 4b were formed by the following methods.

< preparation of transparent resin layer >

A transparent resin sheet of 100 μm thick high crystalline polypropylene was produced by extruding a resin obtained by mixing 100 parts by mass of a high crystalline homopolypropylene resin with 0.5 part by mass of a hindered phenol antioxidant (Irganox 1010; manufactured by BASF), 0.5 part by mass of a triazine ultraviolet absorber (CYASORB UV-1164; manufactured by SUNCHEM) and 0.5 part by mass of a NOR type light stabilizer (Tinuvin XT850 FF; manufactured by BASF) using a melt extruder. Subsequently, corona treatment is performed on both sides of the transparent resin sheet on which the film has been formed so as to set the wetting tension of the surface to 40dyn/cm or more.

< producing patterned Pattern layer and primer layer on raw Material layer >)

On one surface of the polyethylene sheet (raw material layer 7) having a concealing property of 80 μm, pattern printing was performed by gravure printing using a two-liquid urethane ink (V180; manufactured by eastern ink (co.)) to provide a pattern layer 2, and on the other surface of the raw material layer 7, a primer layer 5 was provided.

< adhesion of transparent resin layer to Pattern layer >)

Then, the transparent resin layer 1 was coated with a dry laminating adhesive (Takelac A540; sanchi chemical Co., ltd.) in an amount of 2g/m ² ) And is bonded to the face of the patterned structured layer 2 of the stock layer 7 by dry lamination.

< production of embossed Pattern >)

On the surface of the transparent resin layer 1 of the adhesive sheet, pressing is performed using a mold roll for embossing to provide an embossed pattern 1a.

Preparation of Top coating agent D for surface protective layer 4b

The top coating agents D used in examples 1-1 to 1-4 and comparative examples 1-1 to 1-2 were composed of a thermosetting resin D as a main agent. Thermosetting resin D is an acrylic polymer having a glass transition temperature of about 100deg.C, a mass average molecular weight Mw of about 60,000, and a hydroxyl number of 16. The top coat agent D was prepared by mixing 5 parts of Tinuvin479 (manufactured by BASF) as an ultraviolet absorber, 3 parts of Tinuvin123 (manufactured by BASF) as a light stabilizer, 50 parts of ethyl acetate as a diluting solvent, 15 parts of an inorganic filler L-121 (AGC SI Tech co., manufactured by Ltd) as a gloss adjuster, and 5 parts of Duranate TAP-100 (manufactured by asahi chemical corporation) as a curing agent with 100 parts of a main agent.

< preparation of surface protective layer 4b >

On the transparent resin layer 1 to which the embossed pattern 1a was applied, a coating amount of 10g/m was applied ² The top coating agent D is applied to form the surface protective layer 4b.

The surface protective layers 4a of examples 1-1 to 1-4 and comparative examples 1-1 to 1-2 were formed by the following methods.

Preparation of topcoat agent A, B, C for use in surface protective layer 4a

The top coat agents A, B, C used in examples 1-1 to 1-4 and comparative examples 1-2 were each composed of an ionizing radiation-curable resin A, B, C as a main agent. The ionizing radiation curable resin A is a multifunctional urethane acrylate oligomer having 3 to 15 functional groups, B is a multifunctional urethane acrylate oligomer having 2 to 9 functional groups, and C is a multifunctional urethane acrylate oligomer having 1 to 6 functional groups. To 100 parts of each main agent, 5 parts of Tinuvin 479 (manufactured by BASF) as an ultraviolet absorber, 3 parts of Tinuvin 123 (manufactured by BASF) as a light stabilizer, 8 parts of Silohobic 702 (manufactured by Fuji Silysia Chemical Ltd) as a gloss adjuster, and 50 parts of ethyl acetate as a diluting solvent were mixed to prepare a top coat agent A, B, C.

Comparative example 1-1 >

At a coating weight of 5g/m on the surface of the surface protective layer 4b ² The heat-curable topcoat material D was applied to form the surface protective layer 4a of comparative example 1-1.

Comparative examples 1-2 >

An ionizing radiation-curable top coat agent A, a top coat agent B and a heat-curable top coat agent D were prepared as follows: 6:70 and in a coating weight of 5g/m ² The surface protective layer 4a of comparative examples 1-2 was formed by coating on the surface of the surface protective layer 4 b.

Example 1-1 >

An ionizing radiation-curable top coat agent A, a top coat agent B and a heat-curable top coat agent D were prepared in a proportion of 40:10:50 and at a coating weight of 5g/m ² The surface protective layer 4a of example 1-1 was formed by coating the surface of the surface protective layer 4 b.

Examples 1-2 >

Ionizing radiation-curable top coat agent A, top coat agent B and heat-curable top coat agent D were prepared by mixing 64:16:20 and in a coating weight of 5g/m ² The surface protective layer 4a of examples 1-2 was formed by coating on the surface of the surface protective layer 4 b.

Examples 1 to 3 >

The ionizing radiation-curable top coat agent A and the heat-curable top coat agent D were prepared as a mixture of 80:20 and in a coating weight of 5g/m ² The surface protective layer 4a of examples 1 to 3 was formed by coating on the surface of the surface protective layer 4 b.

Examples 1 to 4 >

Ionization is put awayThe radiation curable top coating agent C and the heat curable top coating agent D were prepared in an amount of 80:20, and at 5g/m ² The surface protective layer 4a of examples 1 to 4 was formed by coating on the surface of the surface protective layer 4 b.

After each of the decorative sheets obtained in examples 1-1 to 1-4 and comparative examples 1-1 to 1-2 was adhered to a wooden substrate using a urethane-based adhesive, the surface hardness was judged by the huffman scratch test/coin scratch test/steel wool friction test. The evaluation results are shown in tables 1 to 3 below.

TABLE 1

TABLE 2

TABLE 3

Hereinafter, the test method of each evaluation test will be briefly described.

< Huffman scratch test >)

In the hofmann scratch test, the surface of each decorative sheet adhered to the wooden base material was scratched at a constant speed for 200g to 2000g of load under a test length of 5cm per 200g of load using a hofmann scratch hardness tester (manufactured by BYK-Gardner corporation), and the load when scratches were generated on the surface of the decorative sheet was shown.

And (3) the following materials: hofmann scratch of 1600g or more

And (2) the following steps: hofmann scratch is more than 1200g and less than 1600g

Delta: the Hofmann scratch is more than 600g and less than 1200g

X: huffman scratch less than 600g

In the huffman scratch test, "verygood", "good", "delta" were acceptable.

< coin scratch test >)

In the coin scratch test, a coin of 100 yen or 10 yen was used, the angle of the coin with respect to the decorative sheet was fixed at 45±1°, and the coin was slid for 5cm in a state of applying a load of 1kg to 5kg (1 to 4kg is 10 yen coin, 5kg is 100 yen coin) to the coin, and whether or not a scratch of 3mm or more was formed on the decorative sheet was determined, and the load when the scratch was formed was expressed as the surface hardness of the decorative sheet.

And (3) the following materials: the scraping rate of coins is more than 3kg

And (2) the following steps: the coin scraping is more than 2kg and less than 3kg

Delta: the coin scraping is more than 1kg and less than 2kg

X: the scraping rate of coins is less than 1kg

In the coin scratch test, "excellent", "" o "," "Δ" were acceptable.

< Steel wool Friction test >)

In the steel wool friction test, steel wool was fixed with a jig in a state of being brought into contact with the surface of each decorative sheet adhered to a wooden substrate, and 500g/cm was applied to the jig ² And friction is carried out at a constant speed under the conditions of 50mm distance and 50 rounds, and whether the surface of the decorative sheet is scratched or not is visually judged. The steel wool was used after being 1cm square by agglomerating Bonstar #0 (manufactured by Japanese steel wool Co., ltd.).

And (3) the following materials: matt change and scratch

And (2) the following steps: it was confirmed that the gloss was slightly changed but no scratch was found

Delta: has a change in gloss and produces a slight scratch

X: has a change in gloss and produces a number of scratches

In the steel wool friction test, "very good", "delta" were acceptable.

As is clear from tables 2 to 3, the decorative sheets of examples 1-1 to 1-4 of the present invention gave excellent mar resistance in good balance.

When the resin composition of the surface protective layer 4a contains 80% or more of the ionizing radiation curable resin or contains a resin having a high crosslink density, the corrosion rate E is small, and as a result, the scratch resistance is particularly excellent.

(example 2)

In examples 2-1 to 2-2 and comparative examples 2-1 to 2-2, the same materials were used except for the transparent resin layer, and were formed by the following methods.

< production of transparent resin layer >

A resin obtained by mixing 100 parts by mass of a high crystalline homopolypropylene resin with 0.5 part by mass of a hindered phenol antioxidant (Irganox 1010; manufactured by BASF), 0.5 part by mass of a triazine ultraviolet absorber (CYASORB UV-1164; manufactured by SUNCHEM) and 0.5 part by mass of a NOR type light stabilizer (Tinuvin XT850 FF; manufactured by BASF) was extruded by a melt extruder using an extruder to prepare a transparent resin sheet of high crystalline polypropylene having a thickness of 100 μm used as the transparent resin layer 1. At this time, the crystallinity of the highly crystalline polypropylene was controlled, and a transparent resin sheet A, B, C, D having the corrosion rate E adjusted was produced.

Examples 2-1 to 2-2 and comparative examples 2-1 to 2-2 were formed by the following methods.

Comparative example 2-1 >

A transparent resin sheet A having a corrosion rate E of 0.047 μm/g was produced.

Example 2-1 >

A transparent resin sheet B having a corrosion rate E of 0.52 μm/g was produced.

Example 2-2 >

A transparent resin sheet C having a corrosion rate E of 1.4 μm/g was produced.

Comparative example 2-2 >

A transparent resin sheet D having a corrosion rate E of 2.1 μm/g was produced.

Subsequently, corona treatment is performed on both sides of each transparent resin sheet on which a film has been formed so that the wetting tension of the surface is 40dyn/cm or more.

Preparation of patterned Pattern layer and primer layer on raw Material layer

A masking polyethylene sheet (raw material layer 7) of 80 μm was pattern-printed on one surface thereof by gravure printing using a two-part urethane ink (V180; manufactured by eastern ink, co.) to provide a pattern layer 2, and a primer layer 5 was provided on the other surface of the raw material layer 7.

< adhesion of transparent resin layer to Pattern layer >)

The transparent resin sheets A, B, C, D having the corrosion rate E adjusted were each coated with a dry lamination adhesive (Takelac A540; manufactured by Sanchi chemical Co., ltd.) by dry lamination method at a coating weight of 2g/m ² ) Is bonded to the surface of the patterned pattern layer 2 of the raw material layer 7.

< production of embossed pattern >)

On the surface of the transparent resin layer 1 of the adhesive sheet, pressing is performed using a mold roll for embossing to apply the embossed pattern 1a.

Preparation of topcoat agent X for surface protective layer 4b

The top coat agent X is composed of a thermosetting resin X as a main agent. Thermosetting resin X is an acrylic polymer having a glass transition temperature of about 100deg.C, a mass average molecular weight Mw of about 60,000, and a hydroxyl number of 16. To 100 parts of the main agent, 5 parts of Tinuvin479 (manufactured by BASF corporation), 3 parts of Tinuvin123 (manufactured by BASF corporation) as a light stabilizer, 50 parts of ethyl acetate as a diluting solvent, 15 parts of an inorganic filler L-121 (AGC SI Tech co., manufactured by Ltd) as a gloss adjuster, and 5 parts of Duranate TAP-100 (manufactured by asahi chemical corporation) as a curing agent were mixed to prepare a top coat agent X.

< preparation of surface protective layer 4b >

On the transparent resin layer 1 to which the embossed pattern 1a was applied, a coating amount of 10g/m was applied ² The top coating agent X is applied to form the surface protective layer 4b.

Preparation of Top coating agent Y for surface protective layer 4a

The top coat agent Y is composed of an ionizing radiation curable resin Y as a main agent. The ionizing radiation curable resin Y is a multifunctional urethane acrylate oligomer having 3 to 15 functional groups.

5 parts of Tinuvin479 (manufactured by BASF corporation), 3 parts of Tinuvin123 (manufactured by BASF corporation) as a light stabilizer, 8 parts of Silohobic702 (manufactured by Fuji Silysia Chemical Co,. Ltd.) as a gloss modifier, and 50 parts of ethyl acetate as a diluting solvent were mixed with respect to 100 parts of the main agent to prepare a top coat agent Y.

< fabrication of surface protective layer 4a >

At a coating weight of 5g/m on the surface of the surface protective layer 4b ² The top coating agent Y is applied to form the surface protective layer 4a.

After each of the decorative sheets obtained in examples 2-1 to 2-2 and comparative examples 2-1 to 2-2 was adhered to a wooden substrate using a urethane-based adhesive, the surface hardness was judged by the huffman scratch test/coin scratch test. In addition, a metal weather resistance test was used to determine weather resistance. The evaluation results are shown in table 4 below.

Note that, since the respective test methods of the huffman scratch test and the coin scratch test are described in embodiment 1, the description thereof is omitted here.

TABLE 4

Hereinafter, a test method for the evaluation test of weather resistance will be briefly described.

< weathering test >

The carbon arc weather resistance test was performed according to JISB7753 using a weather resistance tester (Sunshine Weather Meter (SWOM): suga Test Instruments co., ltd.). Then, the time until cracks or whitening of the surface of each decorative sheet were generated was measured.

And (3) the following materials: weather resistance tester for 2500 hours or more

O: weather resistance tester for more than 2000 hours and less than 2500 hours

Delta: weather resistance tester 1500 hours and less than 2000 hours above

X: weather resistance tester is less than 1500 hours

In the weather resistance test, "verygood" "" delta "was acceptable.

As is clear from Table 4, the decorative sheets of examples 2-1 to 2-2 of the present invention gave excellent mar resistance and weather resistance in good balance.

(example 3)

< common Material >)

In examples 3-1 to 3-10 and comparative examples 3-1 to 3-2, the same materials were used except for the surface protective layer 4 a.

< production of transparent resin layer >

A decorative sheet of the structure of fig. 2 was produced. Specifically, a transparent resin sheet of high crystalline polypropylene having a thickness of 100 μm used as the transparent resin layer 1 was produced by extruding 100 parts by a melt extruder a resin obtained by adding 0.5 parts by mass of a hindered phenol antioxidant (Irganox 1010; manufactured by BASF), 20 parts by mass of a benzotriazole ultraviolet absorber (Tinuvin 328; manufactured by BASF), 20 parts by mass of a hindered amine light stabilizer (CHIMASSORB 944; manufactured by BASF), and 10 parts by mass of a nano nucleating agent to 100 parts by mass of a high crystalline homopolypropylene resin having an isotactic pentad fraction of 97.8%, an MFR (melt flow rate) of 15g/10min (230 ℃), and a molecular weight distribution MWD (Mw/Mn) of 2.3. Then, corona treatment is performed on both sides of the transparent resin sheet to be formed into a film so that the wetting tension of the surface is 40dyn/cm or more. The haze value of the crystalline polypropylene resin of the transparent resin sheet which had been formed into a film was set to 8.5% by controlling the cooling conditions at the time of extrusion film formation.

< nanocrystallization of nucleating agent Using supercritical reverse phase Evaporation >

The following describes a method of nanocrystallization of a nucleating agent using supercritical reverse phase evaporation in this example.

First, 100 parts by mass of methanol, 82 parts by mass of a phosphate metal salt nucleating agent (manufactured by Adeka Stub NA-11, adeka corporation) and 5 parts by mass of phosphatidylcholine were put into a high-pressure stainless steel vessel maintained at 60 ℃ and sealed, and carbon dioxide was injected so that the pressure became 20MPa to be in a supercritical state. Thereafter, 100 parts by mass of ion-exchanged water was injected while vigorously stirring and mixing. After stirring for 15 minutes in a state where the temperature and pressure in the container are maintained, carbon dioxide is discharged to return to atmospheric pressure, thereby obtaining a nucleating agent vesicle having an outer membrane made of phospholipid, in which a nucleating agent is encapsulated.

< fabrication of patterned/hidden layer >)

The obtained transparent resin sheet was used as a transparent resin layer 1, and pattern printing was performed on one surface of the transparent resin layer 1 by using a two-component curable urethane ink (V351: manufactured by Toyo ink Co., ltd.) to form a patterned layer 2, and then a coating amount of 6g/m was applied to the patterned layer 2 ² Masking layer 3 was formed by applying a masking two-component curable urethane ink (V351: manufactured by eastern ink corporation) in a superimposed manner.

< preparation of primer layer >)

Furthermore, the masking layer 3 was coated with a coating amount of 1g/m ² A two-pack curable urethane ink (PET-E, regiuser; manufactured by Dai Ji Kai Co., ltd.) was applied as a primer layer, and a primer layer 5 was formed.

< production of embossed Pattern >)

Next, pressing is performed on the other face of the transparent resin layer 1 using a mold roll for embossing to apply the embossed pattern 1a.

< preparation of surface protective layer 4b >

The coating amount was 10g/m on the surface of the embossed pattern 1a ² A two-part curable urethane top coat (TD 365UR varnish, Z202 curing agent; all manufactured by Toyo ink Co., ltd.) was applied.

< preparation of surface-treated Filler >

The surface-treated inorganic fine particles NVC-X1 used in each example and each comparative example were obtained by surface-treating inorganic fine particles (L-121:AGC SI Tech Co, manufactured by Ltd.) with a surface-treating agent having an OH group at the end.

The surface treatment is carried out by a dry method. Specifically, 100 parts by mass of L-121 (inorganic fine particles) was put into a Henschel mixer having a sprayable nozzle, and 10 parts by mass of a surface treatment agent was sprayed while stirring, so that the inorganic fine particles reacted with the surface treatment agent.

< preparation of surface protective layers 4a, 4b >)

The surface protective layer 4a is formed using a top coating agent E to a top coating agent H.

< Top coating agent used for surface protective layer 4a >

The top coating agent is a top coating agent E, a top coating agent F, a top coating agent G and a top coating agent H.

The top coat agent E and the top coat agent F are each composed of an ionizing radiation curable resin (ionizing radiation curable resin) E, F as a main component, and the top coat agent G and the top coat agent H are each composed of a thermosetting resin (thermosetting resin) G, H as a main component.

The ionizing radiation curable resin E is a multifunctional urethane acrylate oligomer having 3 to 15 functional groups, and the ionizing radiation curable resin F is a multifunctional urethane acrylate oligomer having 2 to 9 functional groups.

The thermosetting resin G is an acrylic polyol having a glass transition temperature of about 100deg.C, a mass average molecular weight Mw of about 50,000 and a hydroxyl number of 15, and the thermosetting resin H is an acrylic polyol having a glass transition temperature of about 45deg.C, a mass average molecular weight Mw of about 150,000 and a hydroxyl number of 15.

To each of the top coat agent E, the top coat agent F, the top coat agent G, and the top coat agent H, 100 parts of each of the ionizing radiation curable resin E, the ionizing radiation curable resin F, the thermosetting resin G, and the thermosetting resin H was added and mixed 5 parts of Tinuvin 479 (manufactured by BASF corporation), 3 parts of Tinuvin 123 (manufactured by BASF corporation), which is an ultraviolet absorber, 50 parts of ethyl acetate, which is a diluent, and 5 parts of Duranate TAP-100 (manufactured by asahi chemical corporation), which is a curing agent, when the top coat agent G and the top coat agent H are used.

< Top coating agent I used for surface protective layer 4b >)

The top coating agent used for the surface protective layer 4b is a top coating agent I.

The top coat agent I is composed of a resin (thermosetting resin) I whose main agent is a thermosetting type.

The thermosetting resin I is an acrylic polyol having a glass transition temperature of about 100deg.C, a mass average molecular weight Mw of about 40,000, and a hydroxyl number of 12.

To the top coat agent I, 5 parts of Tinuvin479 (manufactured by BASF) as an ultraviolet absorber, 3 parts of Tinuvin123 (manufactured by BASF) as a light stabilizer, 50 parts of ethyl acetate as a diluting solvent, 15 parts of an inorganic filler L-121 (AGC SI Tech co., manufactured by Ltd) as a gloss adjuster, and 5 parts of Duranate TAP-100 (manufactured by asahi chemical Co., ltd) as a curing agent were mixed with 100 parts of a main agent.

Example 3-1 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 50:50 and 8 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layer 4a of example 3-1 was formed.

Example 3-2 >

The ionizing radiation curable top coat agent E and top coat agent F and the heat curable top coat agent G were mixed with 40:40:20, and 8 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layer 4a of example 3-2 was formed.

Comparative example 3-1 >

Top coat agent E and top coat agent F curable by ionizing radiationAnd a thermosetting top coating agent H at 40:40:20, and 8 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layer 4a of comparative example 3-1 was formed.

Comparative example 3-2 >

The ionizing radiation-curable top coat agent E and the top coat agent F and the heat-curable top coat agent G were mixed with 30:30:40, and 8 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layer 4a of comparative example 3-2 was formed.

Examples 3 to 3 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and adding no inorganic fine particles, and applying the obtained coating liquid at a coating weight of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layer 4a of example 3-3 was formed.

Examples 3 to 4 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 10 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 4 were formed.

Examples 3 to 5 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 10 parts of inorganic fine particles NVC-X1 having an average particle diameter of 8 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied at a coating weight of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 5 were formed.

Examples 3 to 6 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 10 parts of solid was addedInorganic fine particles NVC-X1 having an average particle diameter of 17 μm were subjected to surface treatment, and the resulting coating liquid was applied at a coating weight of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 6 were formed.

Examples 3 to 7 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 10 parts of inorganic fine particles L-121 having an average particle diameter of 5 μm, which were not subjected to surface treatment, were added thereto, and the resulting coating liquid was applied at a coating weight of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 7 were formed.

Examples 3 to 8 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 5 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 8 were formed.

Examples 3 to 9 >

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 20 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 9 were formed.

Examples 3 to 10

The ionizing radiation curable top coat agent E and the top coat agent F were mixed at 25:75, and 35 parts of inorganic fine particles NVC-X1 having an average particle diameter of 5 μm subjected to surface treatment were added thereto, and the resulting coating liquid was applied in an amount of 5g/m ² Coated on the surface of the surface protection layer 4 b. Thus, the surface protective layers 4a of examples 3 to 10 were formed.

Hereinafter, a method for measuring the corrosion rate E of each decorative sheet obtained in examples 3-1 to 3-10 and comparative examples 3-1 to 3-2 will be described.

Average particle diameter D ₅₀ Polygonal =1.2 μmThe alumina powder was dispersed in water to prepare a slurry containing 3 mass% of the polygonal alumina powder with respect to the total mass of the slurry. The decorative sheet was fixed to the base, and the projected distance between the decorative sheet and the nozzle for spraying the slurry was set to 4mm. The nozzle diameter of the nozzle was 1mm×1mm. A slurry containing polygonal alumina powder is ejected from a nozzle, and decorative sheets fixed on a base are sequentially etched away from a surface protective layer. By etching the existing Si wafer under the same test conditions in advance, the standard projection force X was obtained from the displacement etched away with respect to the ejection amount of the slurry (i.e., the depth etched away when 1g of the slurry was ejected), and the ejection intensity at this time was determined from this value. In this example using polygonal alumina powder, the projection force when 6.360 μm/g was etched away with respect to the conventional Si wafer was set as the standard projection force X.

In the present example, in the case of polygonal alumina powder, the projection force was x=1/100 (projection force when 0.064 μm/g was etched away with respect to the conventional Si wafer).

After the corroded portion was washed with water, the corroded depth, i.e., the corrosion depth Z, was measured.

The etching depth Z was measured by a stylus surface shape measuring instrument (made by Kagaku Kogyo Co., ltd./model PU-EU 1/stylus tip R=2μm/load 100. Mu.N/measurement magnification 10,000/measurement length 4 mm/measurement speed 0.2 mm/sec). More specifically, first, slope correction is performed using both end reference regions A, B which are not worn out in the measured length. Next, the fall from the regression line as a reference to the abrasion trace center portion C (average value of 50 μm width) was measured. Next, the difference between the drop data at the time of 0g projection and the drop data at each projection amount was obtained, and the etching depth Z was obtained. From each data of the obtained projection amount-etching depth Z, an etching progress chart and an etching rate profile were prepared. The depth of corrosion Z is thus determined.

In the present embodiment, the above-described etching process and the shape measurement by the above-described shape measuring instrument are repeatedly performed a predetermined number of times (N times), and N times of shape measurement data are obtained.

In this example, the erosion rate E (μm/g) was calculated using the projected particle amount X' (g) and the erosion depth Z (μm) calculated from the above-described projection force.

Further, after each of the decorative sheets obtained in examples 3-1 to 3-10 and comparative examples 3-1 to 3-2 was adhered to a wooden substrate using an adhesive of urethane type, the surface hardness was judged by the huffman scratch test/coin scratch test/steel wool abrasion test. The degree of whitening on the surface of each of the decorative sheets obtained in examples 3-1 to 3-10 and comparative examples 3-1 to 3-2 was also determined. The evaluation results are shown in tables 5 to 8 below.

In embodiment 1, since the respective test methods of the huffman scratch test, the coin scratch test, and the steel wool abrasion test have been described, the description thereof is omitted here.

Hereinafter, a test method of the whitening evaluation test will be briefly described.

< whitening measurement >)

In the whitening measurement, a Gloss value of the surface of the decorative sheet was measured at an incident angle of 60 ° using a hand-held Gloss meter "Gloss chemical" IG-320 manufactured by horiba, ltd.

O: no whitening occurred (gloss value less than 1.0)

X: whitening (gloss value of 1.0 or more)

In this whitening measurement, "Σ" is acceptable.

TABLE 5

TABLE 6

TABLE 7

TABLE 8

As is clear from tables 5 to 8, the decorative sheets of examples 3-1 to 3-10 of the present invention gave excellent mar resistance in good balance.

When the resin composition of the surface protective layer 4a contains 65% or more of an ionizing radiation curable resin or a thermosetting resin composed of a rigid skeleton, the corrosion rate E is small, and particularly, huffman scratch and steel wool friction test are excellent results.

Further, when the inorganic filler added to the surface protective layer 4a is subjected to surface treatment and the average particle diameter is proper or the addition amount is proper, the static friction coefficient is small and the resistance is small, and therefore, similarly, the huffman scratch and the steel wool friction test are excellent results in particular.

Further, under the condition that inorganic fine particles are contained in the surface protective layer 4a, huffman scratch results are excellent.

The decorative sheets according to examples 3-1 to 3-9 of the present invention have excellent scratch resistance and can reduce whitening of the surface.

The decorative sheet of the present invention is not limited to the above-described embodiments and examples, and various modifications can be made within a range not impairing the features of the present invention.

Description of the reference numerals

1 transparent resin layer

1a embossed pattern

2 pattern embossing layer

3 concealing layer

4 surface protective layer

4a surface protective layer (1 st surface protective layer)

4b surface protective layer (2 nd surface protective layer)

5 primer layer

6 adhesive layer

7 raw material layer

8 adhesive resin layer

Claims

1. A decorative sheet comprising a raw material layer, a transparent resin layer and a surface protective layer in this order, characterized in that,

the surface protection layer is composed of a plurality of layers,

when the surface protective layer located on the outermost surface among the surface protective layers is taken as the 1 st surface protective layer, and the surface protective layer located under it is taken as the 2 nd surface protective layer,

the 1 st surface protection layer includes: an ionizing radiation-curable resin having a corrosion rate E of not less than 1 and not more than 0.10 mu m/g and not more than 0.45 mu m/g, and a thermosetting resin having a corrosion rate E of not less than 1 and not more than 0.30 mu m/g and not more than 0.6 mu m/g, as measured by using polygonal alumina particles having an average particle diameter (D50) of not less than 1.2 mu m,

the mass ratio of the ionizing radiation-curable resin to the thermosetting resin (ionizing radiation-curable resin/thermosetting resin) is 95/5 to 40/60,

the transparent resin layer contains a crystallization nucleating agent after vesicular treatment by a supercritical reverse phase evaporation method.

2. The decorative sheet according to claim 1, wherein,

the corrosion rate E of the 1 st surface protection layer is in the range of 0.2 μm/g to 0.45 μm/g.

3. The decorative sheet according to claim 1 or 2, wherein,

the ionizing radiation curable resin as the 1 st surface protective layer includes 1 or more components having 6 or more functional groups and a mass average molecular weight of 1,000 or more.

4. A decorative sheet comprising a raw material layer, a transparent resin layer and a surface protective layer in this order, characterized in that,

the surface protection layer is composed of a plurality of layers,

using the average particle diameter (D ₅₀ ) The corrosion rate E of the 1 st surface protective layer measured on the basis of polygonal alumina particles of 1.2 μm is in the range of 0.1 μm/g to 0.4 μm/g,

5. The decorative sheet according to any one of claims 1 to 4,

the thickness of the 1 st surface protection layer is in the range of 2 μm to 7 μm,

The thickness of the 2 nd surface protection layer is in the range of 2 μm to 14 μm,

the thickness of the surface protection layer as a whole is in the range of 4 μm to 21 μm.

6. A decorative sheet comprising a raw material layer, a transparent resin layer and a surface protective layer in this order, characterized in that,

the corrosion rate E of the transparent resin layer, measured using polygonal alumina particles having an average particle diameter (D50) of 1.2 μm, is in the range of 0.05 μm/g to 2 μm/g,

7. The decorative sheet according to any one of claims 1 to 6, wherein,

the corrosion rate E of the transparent resin layer, measured using polygonal alumina particles having an average particle diameter (D50) of 1.2 μm, is in the range of 0.05 μm/g to 2 μm/g.

8. The decorative sheet according to any one of claims 1 to 7,

the corrosion rate E of the transparent resin layer is in the range of 0.1 μm/g to 2 μm/g.

9. The decorative sheet according to any one of claims 1 to 8, wherein,

the static friction coefficient [ mu ] s of the decorative sheet (according to JISK7 125) is in the range of 0.25 to 0.5.

10. The decorative sheet according to any one of claims 1 to 9, wherein,

the thickness of the transparent resin layer is in the range of 40 μm to 170 μm.

11. The decorative sheet according to any one of claims 1 to 10, wherein,

the surface protective layer contains an inorganic filler,

the average particle diameter of the inorganic filler is in the range of 1 μm to 10 μm,

the inorganic filler is at least one of alumina, silica, aluminosilicate, glass, boehmite, ferric oxide, magnesium oxide and diamond.

12. The decorative sheet according to claim 11, wherein,

the surface protection layer is composed of a plurality of layers,

the content of the inorganic filler is in a range of 1 to 20 parts by mass relative to 100 parts by mass of the resin constituting the 1 st surface protective layer.

13. The decorative sheet according to claim 11 or 12, wherein,

the inorganic filler is subjected to surface treatment.

14. The decorative sheet according to claim 13, wherein,

The surface treating agent for treating the surface of the inorganic filler is at least one of a surfactant, a fatty acid metal salt, a silane coupling agent, organosilicon, wax and modified resin.

15. The decorative sheet according to any one of claims 11 to 14,

the surface protection layer is composed of a plurality of layers,

the surface treatment agent for treating the surface of the inorganic filler has a reactive group that reacts with the main agent resin constituting the 1 st surface protective layer.

16. The decorative sheet according to claim 15, wherein,

the surface treatment agent for treating the surface of the inorganic filler is a surface treatment agent-encapsulated vesicle obtained by encapsulating the surface treatment agent in a vesicle by a supercritical reverse phase evaporation method.

17. The decorative sheet according to any one of claims 1 to 16,

the decorative sheet does not contain vinyl chloride resin.

18. The decorative sheet according to any one of claims 1 to 17, wherein,

the surface protection layer is composed of a plurality of layers,

the ionizing radiation-curable resin is contained in an amount of 65 parts by mass or more and 100 parts by mass or less in 100 parts by mass of the resin constituting the 1 st surface protective layer.